24 cockerell: on the Jamaican species of veronicella. 



represents the variations of but one species, V. sloanii, and that 

 V. virgata, Ckll., must be reduced to V. sloanii var. virgata. With 

 the details given below, the reader can form his own opinion as to 

 the correctness of these conclusions. 



Notwithstanding so much variability, the species V. sloanii, as 



now defined, should be easy of recognition. The following characters 



appear to be quite constant and of specific value in V. sloanii : — 



(i.) The under-side is always free from spots or markings of any 



kind, whereas true occidentalism Guild., from the Lesser 



Antilles, has some spots beneath. 



(2.) The sole never projects from behind the body, as it does in 



one or two of the continental species. 

 (3.) The filiform glands are less than 10 mm. long, whereas in 



dissimilis and floridanus they are considerably longer. 

 (4.) The penis is always long, cylindrical, with the end slightly 

 bulbous and the orifice terminal. It thus entirely differs 

 from that of such species as V. portoricensis. 

 (5.) The filiform glands are always more than 10 in number, thus 



differing from V. morchii and V. dubia. 

 (6.) The female orifice is always postmedian, thus differing from 

 the continental V. nigra, &c. 

 Aside from these constant characters, we find the most extraordinarily 

 variability, both as to colour, size, and anatomical features. 



Variable Characters. 

 (1.) Size: sexually mature examples (in alcohol) range from 36 to 

 71 mm. in length, from which it seems certain that the 

 slugs grow after reaching sexual maturity. 

 a. Nos. jq, 7, 21, 20, 17, 22, and 16 are less than 40 mm. long. 

 /'. Nos. 5, 8, 11, 10, 24, 13, 18, and 14 are 40 or over, but less 

 than 50 mm. long. 



c. Nos. 9, 4, 1, and 3 are 50 or over, but less than 56 mm. long. 



d. No. 2 is 7 1 mm. long. 



A comparison of the descriptions will show that size 

 cannot be correlated with other characters so as to serve 

 for specific distinction. It is, however, remarkable that 

 the largest specimen (71 mm.) has the shortest (3^ mm.) 

 filiform glands. 



(2.) Shape : the shape varies somewhat in the contracted slugs, but no 

 essential difference is noticed between any of the specimens. 



(3.) Colour: contrary to the opinion of some authors, colour seems 

 as useful as most other characters in distinguishing species 

 and races of Veronicella ; but there is great variability, and 



